Mutant-type glucose dehydrogenase and use thereof

The present invention provides a mutant-type glucose dehydrogenase having glucose dehydrogenase activity and having decreased reactivity with xylose, wherein said mutant-type glucose dehydrogenase comprises a mutant-type α-subunit comprising an amino acid sequence of 520 to 550 amino acids comprising an amino acid sequence of 520 to 550 amino acids comprising SEQ ID NO: 21, SEQ ID NO: 22, SEQ ID NO: 23, SEQ ID NO: 24 and SEQ ID NO: 25 in this order from N-terminus to C-terminus, except that one or more amino acid residue(s) selected from the group consisting of the glycine at position 10 in SEQ ID NO: 23, the histidine at position 4 in SEQ ID NO: 24, and the asparagine at position 4 in SEQ ID NO: 25 is/are substituted with another/other amino acid(s).